Process of reducing metals.



witnmoeo No. 826,557. PATENTBD JULY 24', 1906.

G. L. FOGLER.

PROCESS OF REDUOiNG METALS.

APPLIGATION FILED AUG.19, 1904.

@luuenfqz UNITED STATES PATENT ()FFIGE GEORGE LUTHER FOGLIJR, OF PITTsBURG, PENNSYLVANIA,

PROCESS OF m-zoucme METALS.

Q No. 826,557.

Specification of Letters Patent.

Patented. July 24, 190 6.

To all whom/ it may concern.-

Be it known that I, GEORGE LUTHER Foe- LER, a citizen of the United States, resid' at Pittsburg, in the County of Allegheny an State of Pennsylvania, have invented certain new and useful Im rovements in Processes for Reducing Meta and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon,

which form a part of this specification.

This invention has for its object the reduction of iron and other metals from their ores or oxids. under diminished pressure by the action of a highly-heated reducing gas or gases exteriorly produced.

As the operation of the smelting of iron is now practiced the ores are fed into blast-furnaces, together with solid fuel and flux, and the reduction is effected through the action of the burning fuel or the products thereof produced after ignition by the blast of air which is also introduced into the furnace.

Under the conditions of pressure em'sting in blast-furnaces the action of these products is limited, since by the combustion of the carbon and hydrocarbons C0,, C0, and H,O

- are produced, and under the conditions of I pounds.

pressure which obtain according'to Sir L. ell at a tem erature near whiteness iron will be oxidize by a mixture of CO and CO in e ual proportions, while ferrous oxid cannot e reduced when the mixture of CO, and CO contains as much as eleven per cent, by volume, of C0,. Water-vapor also oxidizes iron at high temperatures under pressure.

It is well known that with a change in pressure the chemical reactions taking place at a certain temperature are greatly modified, and I have taken advantage of this fact to utilize gaseous fuel produced outside of the reduction-furnace and forced into the charge through the twyers under pressure, by which to set free the metal from its com- Each t er is supplied with the superheated gases by a pipe projecting into its outer end and leaving between the gas pipe and twyer an annular space in communication with the atmospheric air of such size as to produce the greatest increase in the temperature of the gases without impairing their action in reducing the ores. The gases which under the conditions of increased pressure and insuflicient air-supply for complete combustion pass into and through the reduction zone expand and flow rapidly upward both because of the greater porosity of the upper charge and because of the partial vacuum which is maintained at the upper or takeplace, and therefore when these condi tions exist fluxes of a nature and in the proportions best suited to remove these impurities must be employed.

' To carry out my process, using as an illustration an ore of iron, I make use of a stackfurnace, which permits of the charges of ore and flux being fed in at the top and-the metal and sla being discharged at the bottom, or any o ier equivalent structure.

The accompanying drawing shows a pre- I ferred form 0 furnace adapted to carry out the details of my process.

This "furnace (designated b the letter A) is shown in side elevation an partly in section.

' B denotes the bell and hopper charging de c is the slag-vent, and dthe metal-discharging vent.

E is a gas-outlet leading through the downcomer F and the purifier G to the exhaust mechanism H.

I is the reducing-gas heater through which the exteriorly-produced gas is fed'throughpipe K and twyer L to the furnace. The pipe '1'- feeds gas to heatthe reducing-gas 1n the heater I, and air is drawn into the twyer .L around the pipe K. By these means the furnace is heated to'the desired temperature, and the supplies of gas and air are so regulated as to maintain this temperature while the reducing gas or gases are supplied to the furnace. The exhaust is then applied, the

charge of ore and flux fed in, and the fusion and reduction proceeds until the molten metal and slag are removed. Thus the operation may be a continuous-or a discontinuous one.

I am aware that it is well-known practice to reduce metals by means of gas exteriorly produced, which is passed over the mass when heated; but heretofore the containing vessel has been heated from the outside, whereas as I practice the art the vessel is heated on the inside.

What I claim, and desire to secure, is

The herein-described continuous process of smelting ores which consists in forcing reviously-heated reducing-gases into a red tion zone maintained in the ore, furnishing a supply of air insufficient to efiect complete combustion around the gas-supply whereby the incompletely-burning ases reduce the 20 charge and rapidly leave the reduction zone; continuously maintaining the reducin atmosphere in the furnace, drawing 0 the products of the smelting process and supplyfresh ore and flux from time to time.

n testimony whereof I affix'my signature 0 in presence of two witnesses.

GEORGE LUTHER FOGLER.

Witnesses:

P. J. MoCALL, P. Jos. Hess. 

